WT2605-16S Bluetooth Audio Chip
High‑Quality Audio Codec with 120MHz DSP, 16‑bit DAC/ADC & UART Control
The WT2605-16S is a high‑quality Bluetooth audio codec chip designed specifically for audio applications. Powered by a 32‑bit DSP running at up to 120MHz, it features a 16‑bit DAC with 96dB SNR and a 16‑bit ADC with 90dB SNR for superior audio quality. With UART control (115200 baud), SPI‑Flash support up to 128Mbit, and a compact SOP16 package, it is ideal for wireless audio, streaming, and voice applications.
- 32‑bit DSP – 120MHz for smooth audio processing
- 16‑bit DAC – 96dB SNR for pristine audio output
- 16‑bit ADC – 90dB SNR for clear audio input
- Bluetooth audio – wireless streaming
- UART control – 115200 baud, simple commands
Key Features
Audio Specifications
| Parameter | Value |
|---|---|
| DAC Resolution | 16‑bit |
| DAC SNR | 96 dB (A‑Weighted) |
| DAC THD+N | ‑86 dB |
| DAC Max Output | 2.6 Vpp (32Ω loading) |
| ADC Resolution | 16‑bit |
| ADC SNR | 90 dB (A‑Weighted) |
| ADC THD+N | ‑87 dB |
| Sample Rates | 8, 11.025, 12, 16, 22.05, 32, 44.1, 48 kHz |
UART Command Set
| Command | Function | Description |
|---|---|---|
| A0 | Index Playback | Play audio by index in SPI‑Flash |
| AA | Pause / Resume | Toggle pause/playback (Flash, SD, USB, Bluetooth) |
| AB | Stop | Stop current playback |
| AC | Next Track | Play next track |
| AD | Previous Track | Play previous track |
| AE | Volume Control | Set volume (0–31, default 26) |
| AF | Playback Mode | Normal / Single loop / All loop / Random |
| C1 | Query Volume | Get current volume level |
| C2 | Query Work Status | Play / Stop / Pause |
| CC | Query Flash File Count | Get total audio files in Flash |
Protocol format: 7E + Length + Command + Parameters + Checksum + EF. Return code 00 = OK, 01 = FAIL, 02 = File not found.
Technical Specifications
| Parameter | Value / Condition |
|---|---|
| Package | SOP16 |
| Processor | 32‑bit DSP, up to 120MHz |
| Operating Voltage | 3.0V – 5.0V |
| DAC SNR | 96 dB (A‑Weighted) |
| ADC SNR | 90 dB (A‑Weighted) |
| Audio Formats | MP3, WAV |
| Sample Rates | 8–48 kHz |
| External Flash | SPI‑Flash up to 128Mbit |
| Control Interface | UART (115200 baud) |
| Volume Levels | 31 (0–31) |
| Bluetooth Name | BT‑WT2605‑16S (default) |
| Crystal | 26MHz, 7.5/9pF, ±10PPM |
| Operating Temperature | ‑40°C ~ +85°C |
| IO Drive Capability | 8 mA |
Pin Functions (SOP16)
| Pin | Name | Function |
|---|---|---|
| 1 | BT_ANT | Bluetooth antenna |
| 2 | OSCI | 26MHz crystal input |
| 3 | OSCO | 26MHz crystal output |
| 4 | USB DM / SDDAT | USB D− / SD card data |
| 5 | USB DP / SDCLK / SPICLK | USB D+ / SD clock / SPI‑Flash clock |
| 6 | SDCMD / SPICS | SD card command / SPI‑Flash chip select |
| 7 | MIC+ / AUX_L / SDDAT / SPIDO | MIC input / AUX input / SPI‑Flash data out |
| 8 | DACL | DAC left channel output |
| 9 | GND | Ground |
| 10 | GND | Ground |
| 11 | NC | Not connected |
| 12 | ADKEY / IR | Analog key input / IR input |
| 13 | VDDIO | 3.3V power output |
| 14 | VBAT | Power input (3.0–5.0V) |
| 15 | TXD | UART transmit |
| 16 | RXD | UART receive |
SPI‑Flash and SD card share the same interface – they cannot be used simultaneously.
Application Scenarios
Why Choose WT2605-16S
Frequently Asked Questions
What is the WT2605-16S?
WT2605-16S is a high-quality Bluetooth audio codec chip with a 32-bit DSP up to 120MHz, 16-bit DAC (96dB SNR) and 16-bit ADC (90dB SNR), UART control, and SPI-Flash support, all in a compact SOP16 package.
What is the Bluetooth name and version?
The default Bluetooth name is ‘BT-WT2605-16S’. The chip supports Bluetooth audio streaming with 26MHz crystal (7.5/9pF, ±10PPM).
What storage media are supported?
It supports external SPI-Flash up to 128Mbit. SD card and SPI-Flash share the same interface and cannot be used simultaneously.
What is the audio quality?
It features a 16-bit DAC with 96dB SNR and a 16-bit ADC with 90dB SNR, delivering high-quality audio input and output.
What control interface does it use?
It uses a standard UART interface with default baud rate 115200. Commands follow a 7E … EF protocol for playback, volume, and mode control.
What is the operating voltage range?
The chip operates from 3.0V to 5.0V, compatible with both 3.3V and 5V systems.
What are the audio sampling rates supported?
It supports 8, 11.025, 12, 16, 22.05, 32, 44.1, and 48 kHz sampling rates.
Does it support battery level display?
Yes. When connected via Bluetooth, the chip displays battery level: 100% at 4.2V, 20% at 3.3V. This feature can be disabled upon request.
What are the typical applications?
Wireless broadcasting, intercom systems, multimedia teaching equipment, network radios, navigation systems, medical devices, elevator floor announcers, smart home, smart city, smart agriculture, charging stations, and voice recorders.
What is the recommended Bluetooth range?
The recommended Bluetooth range is within 10 meters for optimal performance. Proper PCB layout and antenna design are required.
Important: A 26MHz crystal (7.5/9pF, ±10PPM) is required for Bluetooth operation. SPI‑Flash and SD card share the same interface – they cannot be used simultaneously. The DACL output should be routed away from RF and high‑current traces. For ESD protection, a TVS diode (<0.45pF) is recommended near the antenna. The chip defaults to 31‑level volume (26 on power‑up). The UART baud rate is fixed at 115200.
